Thermostatic trap



,Jan. 17, 1928. 1,656,373

J. L., FITTS THERMOSTATIC TRAP FiledvJune 13, 1925 2 Sheets-Sheet l[We/112v". James 05m F/f/s.

Jan. 17, 1928.

J. L. FITTS THERMOSTATIC TRA 2 Sheets-Sheet 2 Filed June 13, 1925 M/forney.

Patented Jan. 17, 1923.

JAMES LOGAN FITTS, 0F MERCHANTVILLE,

NEW JERSEY, ASSIGNOB '10 WARREN WEBSTER & COMPANY, A CORPORATION OF NEWJERSEY.

THERMOSTATIC TRAP.

Application filed June 13, 1925. Serial No. 88,858.

Thermostatic traps for steam heating and other purposes and employed forpermitting the escape of water of condensation and air while restrictingor preventing theescape of steam have heretofore been constructed with athermostatically operated valve piece, the expansible member of whichcomprises a bellows-like structure Whose lower part is provided with avalve piece and its upper part attached to the cap or bonnet of thesurrounding body whereby the thermostat-1c member is rigidly secured tothe casing. as a whole; but it frequently happens that where the bellowsis subjected to high temperature and pressure, severe strains occur fromwater hammering which cause it to fail to function properly, and inwhich case, it is necessary to replace the expansible member wlthaccuracy and facility, without removing the valve body from itsconnection with the steam and waste pipes.

The object of my invention is to provide a simple and efficient meansfor supportlng the thermostatic member within the valve body andrelatively to the valve seat therein, so as to be accurately positionedto respond to predetermined temperature and pressure conditions, eitheror both, and which supporting means for the thermostatic member isreadily clamped, directly or indirectly, lIl position within the body orcas ing by the cap or bonnet, providing a yreldmgc'ontaet therewith forpositively holding the thermostatic member upon the body in accurateoperative relation irrespective of any var1ations in the positioning ofthe cap or bonnet, relatively to the body, the construction being suchthat the removal of the cap or bonnet permits release and read access toand removal of the thermostatic member and its attached support forrepairs or replacement,

and when in clamped position, the support for the thermostatic memberalways insures a definite predetermined relative positlon between thesupport and the valve seat.

My invention consists of a body or casinghaving a valve seat and adefinitely positioned shoulder or ledge in respect to said seat,combined with a sheet metal disk structure resting upon the saidshoulder or ledge and carrying a thermostatic member with its valvepiece in accurate position with res ect to the valve seat of the body,and in w ich further, the plate is clamped upon the shoulder or ledge bymeans of a cap or bonnet attached to the casing or body, an interposedyielding structure being positioned between the cap or bonnet and thedisk whereby said disk is clamped definitely upon the supportingshoulder or ledge (and the valve piece is accurately positioned withrespect to the valve seat), irrespective of any small variation orirregularity of the clamping action of the cap or bonnet with the casingor body.

My invention also consists of a thermostatically operated trapcharacterized by raving the supported end of the thermostatic memberprovided with a suspension plate having spring portions by which,through the agency of the cap or bonnet,-the plate is clamped or held indefinite correlation with respect to the body structure and valve seatthereof, while being wholly enclosed within the casing.

My improvements also include the suspension means for the thermostaticmember, when made of disk-like form resting upon a shoulder or ledgewithin the body to definitely limit the distance of suspension inrespect to the valve seat, and provided with spring portions bent to oneside of the plate of the disk-like suspension means, said springportions clamped by the cap or bonnet against movement away from thevalve seat but, at the same time, permitting the upper part of thethermostatic member and disk-like suspension means secured theretoslightly moving in a direction away from the valve seat in case of heavywater hammering.

My invention also comprehends details of construction which, togetherwiththe features above stated, are fully described here inafter and morespecifically defined in the claims.

Referring to the drawings: Fig. 1 is a vertical section of athermostatic trap and embodying my improvements; Fig. 2 is a lan view ofthe suspension disk thereof; ig. 3 is a perspective view of thesuspension disk; Fig. 4 is a verticalsection of the upper part of athermostatic trap showing a modification of my invention; Fig. 5 1s aplan view of the sheet metal suspension plate before being bent intofinal shape for use in the structure of Fig. 4; Fig. 6 is a perspectiveview of the suspension plate shown in Fig. 4; Fig. 7 is a cross sectionof a high pressure thermostatic trap embodying my lmprovements; and Fig.8 is a lan view of the thermostatic member and suspension ate.

p Referring more specifically to Fig. 1, 2 is the body casing of thetrap and is provided with an inlet port 3 open into the side of the bodyand an outlet port 4 having a perforated valve seat 5 arranged at thebottom of the valve body. 6 represents the cap or bonnet and isdetachably secured to the upper open end of the body 2 through themedium of an inwardly directed circular flange 13 screw threaded at 11into connection with the upper end of the body. The depth of thecircular flange 13 is less than the depth between the open end of thebody and the internal shouldered portion '12 thereof so that there isprovided an annular groove or channel at 14 between said shoulderedportion 12 and the inner end of the flange 13.

The thermostatic member 3 is preferably of bellows constructioiuand isfitted at the bottom with a conical valve piece 7 and its upper end isclosed by the usual plate 9 having a projecting screw threaded stud 10.15 is a suspension plate which is provided with a central aperture 16through which the screw threaded stud 10 extends, and said suspensionplate is tightly clamped upon the top plate of the thermostatic member 8by means of a nut 18. In practice, the distance between the suspensionplate 15 and the end ofthe valve piece 7 is definitely and accuratelyprovided by screwing the conical valve piece 7 into the lower end of thethermostatic member 8 and securing it in such adjustment by a transversepin 7.

The body 2 is counter-bored to provide the annular groove 14 andshoulder 12 in an accurate manner so that the distance between the saidshoulder and the surface of the valve seat 5 is exactly provided; and.furthermore, the relation between the conical valve piece 7 and thediameter of the aperture in the valve seat 5 is properly proportioned soas to make the valve accurately responsive when the thermostatic memberand its plate is ositioned within the body and definitely c amped uponthe annular shoulder 12 thereof.

The plate 15 has its perimeter made with radial slots 17 by whichtongues 17 are provided, the same being bent upwardly and radially toform a plurality of spring tongues above the normal plane of the plateand which are pressed downward toward the late by the flange 13 of thecap or bonnet.

n this manner, the accuracy of the thermostatic member within the bodv 2is assured and the plate is positively held down in contact with theshoulder by the spring pressure of the tongues 17 when forced downwardby the action of the cap flange 13. It will be understood that should,for any reason, it

. operative be necessary to replace the thermostatic member, it onlybecomes necessary to remove the cap or bonnet 6, lift out the defectivethermostatic member, replace it by a new member in which the plate ofthe new member rests upon the shoulder, and thereafter clamping theplate in position by the cap or bonnet.

Where the pressure and temperature are high and especially where thevalve is large, there is always more or less liability of the seating ofthe valve piece to cause a water hammering effect in the action of thesurging water within the body 2, and its effect upon the thermostaticmember. This water hammering is due to the seating of the valve piece 7upon its seat and its sudden rise therefrom under the pressuredifl'erential between the contents of the body and the return or wastepipe, and should this water hammering be such as to tend to abnormallyraise the thermostatic member and its associated plate 15 to a minuteextent, the spring tongues 17 would permit sutlicient yielding to removean excessive strain upon the thermostatic member itself. This capacitywill increase the life of the thermostatic member by reducing some ofthe strains which otherwise would come upon the metal of the bellows. Itwill be understood that the pressure above the plate and within the capor bonnet is substantially the same as the chamber of the trap in whichthe thermostatic member is located, because the bent portions to formthe tongues 17 provide spaces to opposite sides of the plate 15 throughwhich the steam or gaseous medium may freelv circulate. In thismanner,-there is no differential permitted between the space above andbelow the suspension plate and consequently the thermostatic member andits suspension plate 15 normally retains the position shown in which theshoulder definitely insures the operating valve piece for accuratecontrol of the escape brought in the valve seat. The suspension plate isshown in Figs. 2 and 3 in addition to the illustration in Fig. 1, andmay be made of any metal which is highly resistant to corrosion andwhich will retain its resiliency at the high temperatures of the steam.I have found that phosphor bronze is satisfactory, also monel metal,cupro nickel alloy, and stainless steel may likewise be employed, andthe latter which is non-corrosive will give the longest life to thedisk.

Referring to Figs. 4. 5 and 6, the general construction and operation ofthe parts are substantially the same as in Fig. 1, but the suspensionplate is modified in construction. In this case, the disk 15 isprovided, as before, with the central aperture 16 and the perimeter witha plurality of radial tongues 17. but these are bent upward and inwardas shown in Figs. 4 and 6 to provide the latter is slit radially as at17 Ill] spring parts which fit into the annular groove 14. The plate 15rests upon the annular shoulder 12 of the body and the spring tonguesare pressed downward by the annular flange 13 of the cap or bonnet 6 toretain the suspension plate in position. To enable these spring tongueparts being kept substantially within the diameter of tlli e disl)(,

1g. 5 but to a less extent than in the cases of F ig. 2. Since thesuspension plate in this case is of a diameter substantially equal tothe diameter of the flange 12 and counter-bore, holes 15 are providedthrough it to permit of the passage of steam or air to equalize thepressure above and below the thermostatic member.

Referring now to the construction shown in Figs. 7 and 8, which is moreespecially useful in high pressure traps, the body portion of the trapis in general similar to the construction shown in Figs. 1 and 4, withthe exception that the upper open part of the body is not screw threadedto receive the cap or bonnet. In this case, the counter bore 14" isquite shallow but provides the annular shoulder 12 as before. The suspension plate 15 is circular and snugly fits the counter-bore so as torest upon the shout dei- 12. The depth of the counterbore 14 issubstantially the thickness of the plate 15. Resting upon the upperannular surface of the body above the counter-bore 14 and partly uponthe suspension plate 15 is an annular gasket or packing ring 17 d whichis preferably of copper and asbestos, as coinmonly-employed for packedjoints, though I do not restrict'myself as to the particular compositionof the gasket. For roperly positioning the gasket, it is manifhst thatthe upper surface of the body may be provided with a counter-bore of amaximum diameter equal to the outer diameter of the gasket. The cap 6fits over the body and has its underside formed with an annular rimwhich directly rests upon the gasket or packing 17 and said cap isclamped down in position upon the gasket by the cap screws 11. A. 'ointof this kind between the cap and the ody is very strong and well suitedto high pressure steam traps.

he suspension plate 15 is provided with a central hole 16 throughwhich'the stud 10 of the thermostatic member 8 passes, and said memberis secured to the plate and slightly spaced from it by an annular washer18 arranged between the shoulder of the top plate 9 of the thermostaticmember and the underside of the suspension plate 15 and by a nut 18screwed upon the stud and clamping the plate down upon thespacing washer18*. The suspension plate 15 is' provided with apertures 15 through thesame whereby the space within the cap and the space within the body arecontinuously tion of this application in communication so that thepressure above and below the plate is equalized. The thermostatic member8 may be of any suitable construction but preferably of the characterillustrated in Letters Patent N 0. 1,235,673, granted to me on August 7,1917, wherein there is a bellows construction corresponding to 8 andhaving at its lower part a conical valve piece 7.

It will be seen that in the structure shown in Fig. 7, the distancebetween the under surface of the suspension plate 15 and the top surfaceof the valve seat 5 is fixed, and that as the thermostatic element iscarried by the .plate the position of the valve in respect to theorifice in the valve seat will always be the same when the parts areassembled with the underside of the plate resting u on the shoulderedportion 12.

With t e construction shown in Fig. 7, it will be seen that replacementsof the interior parts of the trap may very easily be accomplished byremoving the cap screws 11, lifting off the cap 6", removing the ringgasket 17 and lifting out the interior thermostatic member with itsattached valve piece and suspension plate and replacing the thermostaticmember and plate with a new'part and thereafter replacing the gasket andthe cap and bolting the latter tightly'in place upon the body andgasket,and the trap will be found in proper adjustment in respect to the valvepiece 7 and the vali e seat 5. If the valve seat is worn, it is alsoreadily replaceable by unscrewing the old seat and inserting a new one.These replacements may be made without removing the trap from itsconnection with the piping or other apparatus with which it is em loyed.

lVhile the traps embo ying the construcmay be utilized for ordinaryradiator purposes in which from one to ten pounds steam pressure may beused (for which the ty e shown in Figs. 1 and 4 is well suited), tiearticular benefit of the improvement is bad when the parts are used forhigh pressure such as from ten to one hundred pounds which, being large,involves the attachment of the cap or bonnet by cap screws such as inFig. 7, because in this case, the employment of a asket between the bodyand the cap and t e irregularity in clamping the cap in position wouldinterfere with the accurate positioning of the thermostatic memberrelatively to the valve seat if it were not for the fact that theshouldered portion 12 of the counter-bore and the suspension plate ofthethermostatic member absolutely insure the accuracy of .thethermostatic member within the body.

It will now be apparent that I have devised a novel and usefulconstruction which embodies the features of advantage enumerated asdesirable, and while I have in the present instance shown and describedthe preferred embodiment thereof which has 7 been found in practice togive satisfactory and reliable results, it is to be understood that I donot restrict myself to the details, as the same are susceptible ofmodification in various particulars without departing from the spirit orscope of the invention.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In a thermostatic trap, the combination with a body having inlet andoutlet ports the latter provided with a valve seat at the lower part ofthe body and the body further rovided with an annular supporting shouder or ledge lying in a plane above both the inlet and outlet orts, athermostatic member arranged wit 1in the body at a level above the inletport and having at its bottom a valve piece, a suspension plate having adiameter greater than the thermostatic member and seating upon thecentral part of which the thermostatic the shoulder or ledge and tochamber between the cap or bonnet and the plate.

2. The invention according to claim 1, wherein further, the suspensionplate is formed with a pluralit of integra spring portions immediately ajacent to and spaced about its perimeter and so positioned that they maybe put under compression by the cap or bonnet to hold the plate firmlyupon the annular shoulder or ledge of the body.

3. The invention according to claim 1, wherein further, the suspensionplate is provided with spring portions about its perimcter whose endsextend upwardly from the plane of the suspension plate and so positionedthat they may be put under compression by the cap or bonnet to hold theplate firmly upon the annular shoulder or ledge on the body, said springportions being confined to and integral with the plate'near itsperimeter.

4. The invention according to claim 1, wherein the thermostatic membercomprises a bellows having a stud at its upper end extending through andclamped to the suspension plate and provided at its lower end with anadjustable valve piece whereby the distance from the valve plece to thesuspension plate may be definitely adjusted.

In testimony of which invention, I hereunto .set my hand.

JAMES L. FITTS.

